Fix idempotency for RestartPolicy when MaximumRetryCount > 0 (#607)

Before this change, this task:

```ansible
- containers.podman.podman_container:
    # ...
    restart_policy: on-failure:3
    # ...
```

always caused this diff:

```diff
--- before
+++ after
@@ -1 +1 @@
-restart_policy - on-failure
+restart_policy - on-failure:3
```

Signed-off-by: Sebastian Endres <[email protected]>
Co-authored-by: Sebastian Endres <[email protected]>

plugins/module_utils/podman/podman_container_lib.py

@@ -1166,7 +1166,15 @@ def diffparam_read_only(self):
 
     def diffparam_restart_policy(self):
         before = self.info['hostconfig']['restartpolicy']['name']
+        before_max_count = int(self.info['hostconfig']['restartpolicy'].get('maximumretrycount', 0))
         after = self.params['restart_policy'] or ""
+        if ':' in after:
+            after, after_max_count = after.rsplit(':', 1)
+            after_max_count = int(after_max_count)
+        else:
+            after_max_count = 0
+        before = "%s:%i" % (before, before_max_count)
+        after = "%s:%i" % (after, after_max_count)
         return self._diff_update_and_compare('restart_policy', before, after)
 
     def diffparam_rm(self):